Expansible chamber device

ABSTRACT

An expansible chamber device, adapted for operation either as a motor or a pump, having an inner pin and a plurality of outer crank pins rotatable about axes parallel to the axis of the inner pin and spaced at intervals around a circle surrounding the inner pin, with means interconnecting the outer pins and the inner pin and interconnecting the outer pins with one another, a cluster of double-acting cylinder and piston means, one for each outer crank pin, each having its cylinder connected to the inner pin and its piston rod connected to a respective outer crank pin, and means for controlling the supply and exhaust of fluid to and from opposite ends of each cylinder.

O 1, Umte States Patent 11 1 1111 3,786,727 Baumann 1 1 Jan. 22, 1974 EXPANSIBLE'CHAMBER DEVICE 609,748 5/1926 France 91/496 Inventor: Andrew A Baumam, 3810 Bowen 500,875 6/1930 Germany 91/493 St., St. Louis, Mo. 63116 Prtmary ExamtnerW1ll1am L. Freeh Flledi p 1971 Assistant Examiner-Gregory P. LaPointe [21] AppL N0: 183 134 Attorney, Agent, or Firml(oenig, Senniger, Powers &

Leavitt [52] 11.8. C1. 91/493 51 1111.0. F01b 13/01 [57] ABSTRACT [58] Field of Search 91/491, 493, 496, 495, 180, An expansible chamber device, adapted for operation 91/186, 176; 123/42, 43 R, 44 R; 92/117, either as a motor or a pump, having an inner pin and 118, 119; 417/273; 74/86 a plurality of outer crank pins rotatable about axes parallel to the axis of the inner pin and spaced at in- [56] References Cited tervals around a circle surrounding the inner pin, with UNITED STATES PATENTS means interconnecting the outer pins and the inner 3 168 006 2, Bennett 92/118 pin and interconnecting the outer pins with one an l092930 4/1914 fi'x: 123] other, a cluster of double-acting cylinder and piston abs/Z401 6/1971 Johansson....'.::: III: 91/180 means each crank P each having its 1,328,033 1/1920 Chase 91/496 Cylinder connected to the inner P and its Piston rod 1,060,202 4/1913 Taggart.... 91/495 Connected to a respective outer crank pin, and means 2,603,194 7/1952 Hall 91/180 for controlling the supply and exhaust of fluid to and fI'OlTl opposite ends Of each cylinder.

21,119 2/1911 Norway 91/491 18 Claims, 10 Drawing Figures I I 30 q l3 9 13 30 1 vEXPAIISIIBLE CHAMBER DEVICE BACKGROUND OF THE INVENTION This invention relates to expansible chamber devices, and more particularly to such devices having radial cylinder and piston means, adapted for operation either as a fluid motor or a pump.

Reference may be made to such US. Pat. Nos. as

841,766, 988,938, 1,060,202, 1,300,706, 2,603,194 and 2,695,598 in the field of this invention.

SUMMARY OF THE INVENTION Among the several objects of this invention may be notedthe provision of an improved expansible chamber device of the type having radial cylinder and piston means, and which is adapted for operation either as a fluid motor or pump; the provision of a device of this class in which each cylinder and piston means is double-acting; the provision of such a device which, in its embodiment as a motor, is particularly suited for lowspeed high-torque operation, and which may be readily adapted for operation as a pump at higher speeds.

In general, an expansible chamber device of this invention comprises an inner pin, a plurality of outer crank pins rotatable about outer axes parallel to the axis of the inner pin spaced at intervals around a circle surrounding said inner pin, means interconnecting said outer crank pins and said inner pin and interconnecting said outer crank pins with one another, a cluster of cylinder and piston means, one for each outer crank pin, each cylinder and piston means comprising a cylinder element, a piston in the cylinder element and a piston rod element extending from the piston out of one end of the cylinder element, each cylinder and piston means extending outwardly from said inner pin with one of said cylinder and piston rod elements of each cylinder and piston means connected to said inner pin and the other of said elements thereof connected to the respective outer crank pin, and means for controlling the supply and exhaust of fluid to and from opposite ends of each said cylinder elements.

Other objects and features will be in part apparent and in part pointed out hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in elevation with parts broken away, of a hydraulic motor of this invention;

FIG. 2 is an enlarged fragment of FIG. 3 showing a DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIGS. 1 and 3 of the drawings, a first embodiment of this invention, operable as a hydraulic motor, is shown to comprise a first or inner pin 1 and a plurality of outer crank pins each designated 3 rotatable about outer axes each designated 3a parallel to the axis of the inner pin 1 and spaced at intervals around a circle surrounding the inner pin 1. Means constituted by gearing indicated in its entirety by the reference numeral 5 interconnects the outer pins 3 and the inner pin 1 and interconnects the outer pins with one another. At 6 is generally indicated a cluster of double-acting cylinder and piston means each designated 7, one for each outer pin 3. As illustrated, there are five pentagonally arranged outer crank pins 3 and five double-acting cylinder and piston means 7 in the cluster 6. The locations of the five cylinder and piston means are designated A-E in FIG. 1. Each cylinder and piston means comprises a cylinder element designated by the reference numeral 9, a piston 11 slidable in the cylinder element and a piston rod element 13 extending from the piston out of one end of the cylinder element (its outer end as shown). Each cylinder and piston means 7 extends outwardly from the inner pin 1, with one of its elements connected to the inner pin and the other of its elements connected to the respective outer pin 3. As appears in FIGS. 1 and 3, the cylinder element 9 of each cylinder and piston means 7 is connected to the inner pin 1, and the piston rod element 13 of each cylinder and piston means 7 is connected at its outer end to the respective outer crank pin 3. At 15 in FIG. 3 is generally indicated means for controlling the supply and exhaust of fluid to and from opposite ends of the cylinder elements 9 of the cluster 6.

More particularly, the device comprises a housing, generally designated 17, constituting its frame and consisting of two pentagonal cup sections 19 and 21 assembled open-side-to-openside, with a pentagonal partition 23 therebetween dividing the housing into two pentagonal chambers 25 and 27. The inner pin 1 is a crank pin on a central crank comprsing a central gear 29 rotatable in chamber 27 on the central axis of the pentagonshaped housing. This axis and the axis of gear 29 are indicated at 29a in FIG. 4. The gear 29 has a trunnion 31 on one side joumalled by means of a ball bearing 33 in a central opening 35 in the partition, and a trunnion 37 on the other side joumalled by means of a ball bearing 39 in a central opening 41 in the pentagonal side 43 of the .cup 21. The inner crank pin 1 extends out from trunnion 31 in chamber 25 on an axis parallel to and offset from the axis of the central gear 29. Thus, on rotation of the central gear 29, pin 1 rotates in a circular path in chamber 25 about the axis of gear 29, this circular path having a radius equal to the eccentricity of pin 1 relative to the gear axis 2921.

Each outer crank pin 3 is on an outer crank comprising an outer gear 45 rotatable in the chamber 27 and in mesh with the central gear 29. Each outer gear 45 has a trunnion 47 on one side joumalled by means of a ball bearing 49 in an opening 51 in the partition 23 and a trunnion 53 on the other side joumalled by means of a ball bearing 55 in an opening 57 in the pentagonal side 43 of cup 21. Each outer crank pin 3 extends out from the respective trunnion 47 in chamber 25 on an axis parallel to and offset from the axis 3a of the respective outer gear 45. Thus, on rotation of an outer gear 45, the pin 3 thereon rotates in a circular path in chamber 25 centered in the axis 3a of that outer gear with a radius equal to the eccentricity of the pin 3 relative to the outer gear axis 3a. The axes 3a of the five outer gears 45 are parallel to the axis 29a of the central gear 29 and spaced at equal intervals (72 intervals) around the circle centered in the axis 29a of the central gear drawn through the outer gear axes 3a.

The cluster 6 has a central annular hub 59 which is journalled on the inner crank pin 1 for movement in a circular path therewith around the axis 29a of the central gear 29. The cylinders 9 as illustrated are integral with this hub and extend radially outwardly from the hub spaced at equal (72) angular intervals. Each cylinder has a port 61 at its inner end, and a head 63 at its outer end having a port 65. The piston rod 13 of each cylinder extends outwardly from the piston 11 therein through the head 63 and has an anti-friction coupling 67 at its outer end connecting it to the respective outer crank pin. As shown, the cylinder 9 at A extends vertically upwardly from the hub 59, and the coupling 67 on the upper end of the piston rod 13 extending up from this cylinder is guided for sliding movement in a guideway formed by a pair of side guides 69 constituting part of the cluster 6 and extending upwardly at opposite sides of the cylinder 9 at A from a base 71 therefor formed as part of the cluster.

The central gear 29 and outer gears 45 are all identical (thereby having a one-to-one gear ratio)", and the inner crank pin 1 on the central gear 29 and the outer crank pins 3 on the outer gears 45 all have the same throw (eccentricity) with respect to the gear axes. The outer crank pin 3 on each outer gear 45 is so phased with respect to the crank pin 1 on the central gear 29 that each outer crank pin passes through its inner and outer dead center positions at the same instant that the inner crank pin 1 passes through its inner and outer dead center positions relative to the outer crank pin while the outer crank pin is rotating about the axis of the respective outer gear in the opposite direction from the rotation of the inner crank pin 1 about the axis of the central gear. With this phasing, the motion of each cylinder and piston means 9,11,13 as the central gear or crank 29 and the respective outer gear or crank 45 rotate in opposite directions is a parallel linkage type of motion with the cylinder and piston means acting as an extensible and contractible link. Also, the arrangement is such that the outer crank pins 3 on the outer cranks or gears 45 reach their respective dead center positions in sequence, one after another, rather than simultaneously. Thus, as shown in FIGS. 1 and 4, and considering that the central gear 29 is rotating clockwise and each outer gear 45 is rotating counterclockwise, the outer crank pin 3 at position A (the uppermost crank pin) is at its upper or outer dead center position, the inner crank pin 1 is at its lower or outer dead center position with respect to the cylinder 9 at A, and the piston rod 13 of cylinder 9 at A is fully extended (as shown best in FIG. 4). The inner crank pin 1 is about to come into an outer dead center position with respect to the cylinder 9 at B and the outer crank pin 3 at B is about to come into an outer dead center position with respect to the cylinder 9 at B so that the piston rod 13 at B is about to be fully extended. The pin 1 is just past an inner dead center position with respect to the cylinder 9 at C, and the pin 3 at C is just past an inner dead center position with respect to cylinder 9 at C so that the piston rod 13 at C isjust past its fully retracted position and being extended. The pin 1 is about to come into an inner dead center position with respect to cylinder 9 at D and the pin 3 at D is about to come into an inner dead center position with respect to cylinder 9 at D, so that the piston rod 13 at D is about fully rethe outer end of the hub 59 coaxial therewith. This sleeve 73 has a series of radial ports each designated 75 spaced at intervals around a circle adjacent its outer end, with a line 77 connecting each of these ports 75 with the port 65 in the head 63 at the outer end of a respective cylinder 9. There being five cylinders 9, there are five such ports 75 spaced at 72 intervals, and five such lines 77. The sleeve also has another series of five radial ports each designated 70 spaced at 72 intervals around a circle adjacent its inner end, with a passage 81 from each of these ports 79 to a respective port 61 at the inner end of a respective cylinder 9, there being five such passages 81, one for each of the five cylinders At 83 is indicated a distributor, having an outer cylindric shaft section or spool 85 journalled in a bearing 87 in the pentagonal wall 89 of cup 19 coaxially with the central gear 29, a crank arm 91 on the inner end of shaft 85, and an inner cylindric eccentric shaft section or spool 93 which is rotatably fitted in the sleeve 73. The outer shaft section or spool 85, which is adapted to rotate on its own axis in bearing 87, has two axially spaced annular grooves 95 and 97 in its periphery, groove 95 providing an annular pressure. fluid supply chamber and groove 97 providing an annular fluid return chamber. At 99 is indicated a pressure fluid supply line connected to bearing 87 to supply pressure fluid to annular chamber 95, and at 101 is indicated a fluid return line connected to bearing 87 for exit of fluid from chamber 97.

The inner eccentric shaft section or spool 93, which is adapted to rotate with the hub 59 and sleeve 73 around the axis of the central gear 29 and the outer shaft section 85, has an annular groove in its periphery generally indicated at 103 registering with radial ports 75 in the sleeve 73, this groove being divided into fluid pressure supply and return sections 105 and 107 for the cylinder outer ends by two lands 109 and 111 at 180 intervals. Shaft section 93 also has a second annular groove generally indicated at 113 in its periphery registering with radial ports 79 in the sleeve 73, this groove being divided into fluid pressure supply and return sections 115 and 117 for the cylinder inner ends by two lands 119 and 121 at 180 intervals. Passaging 123 in the distributor connects the annular pressure fluid supply chamber 95 to the supply sections 105 and 115, and passaging 125 in the distributor connects return sections 107 and 117 to the fluid return chamber 97.

The arrangement is such that, as the hub 59 and sleeve 73 rotate around the axis of the central gear 29 and the bearing 87, the eccentric shaft section 93 rotates with them around this axis and rotates within the sleeve 73 in such manner that the pressure fluid supply and return grooves 105 and 107 for the cylinder outer ends come successively into communication with ports 75 and the pressure fluid supply and return grooves 115 and 117 for the cylinder inner ends come successively into communication with ports 79. As shown in FIGS. 7 and 8, by way of example, the fluid pressure supply groove 105 for the cylinder outer ends is in communication with the ports 75 at the D and E locations for supplying pressure fluid to the outer ends of the cylinders 9 at the D and E locations. The port 75 at the A location is blocked. The fluid return groove 117 for the cylinder inner ends is in communication with the ports 79 at the D and E locations for return of fluid from the inner ends of the cylinders 9 at the D and E locations. The port 79 at the A location is blocked. The fluid pressure supply groove 115 for the cylinder inner ends is in communication with the ports 79 at the B and C locations for supplying pressure fluid to the inner ends of the cylinders 9 at the B and C locations. The fluid return groove 107 for the cylinder outer ends is in communication with the ports 75 at the B and C locations for return of fluid from the outer ends of the cylinders at the B and C locations. Thus, the pistons at the D and E locations arebeing driven inwardly, and the pistons at the B and C locations are being driven outwardly. As the shaft section 93 rotates within sleeve 73 (in clockwise direction as viewed in FIGS. 7 and 8) fluid is supplied via groove 105 and the port 75 for the outer end of the cylinder at B, and returned from the inner end of the cylinder at B via port 79 and groove 117. Thus, the piston at the B location is driven inwardly. This occurs for the C, D and E pistons in succession, then on the next cycle, the pistons are all driven outwardly. It will be observed that while the B and C pistons are being driven inwardly, for example, the D and E pistons are being driven outwardly. While the C and D pistons are being driven inwardly, the E and A pistons are being driven outwardly, etc.

The following chart shows the sequence of movement of the A-E pistons, i.e., in or out, for the five distributor positions starting with the first position as shown in FIGS. 7 and 8 with lands 109 and 119 blocking the A ports and going through second to fifth positions wherein the lands 109 and 119 successively block the B, C, D and E ports:

PISTON POSITION OF LANDS 1st 2nd 3rd 4th 5th A In In Out Out B Out In In Out C Out Out In In D In Out Out In E. In In Out Out Thus, as indicated aboVe, when the B and C pistons are being driven out, the D and E pistons are being driven in; next, when the C and D pistons are being driven out, the E and A pistons are being driven in; next, when the D and E pistons are being driven out,

and A and B pistons are being driven in; next, when the E and A pistons are being driven out, the B and C pistons are being driven in; and next, when the A and B pistons are being driven out, the C and D pistons are being driven in. It will be observed that when the lands 109 and 119 each cover a port, that particular piston is at its outer dead center position ready to be driven inwardly by the pressure fluid. Also, when the lands 111 and 121 each cover a port, that particular piston is at its inner dead center position ready to be driven outwardly by the pressure fluid.

The driving of the pistons as above noted results in operation of the device as a hydraulic motor involving driving of the outer gears 45 via the outer crank pins 3 and of the inner gear 29 via the inner crank pin 1. Power may be taken off from any one of the gears or any combination of the gears. It will be observed that thecluster 6 of cylinder and piston means 7 (five in all) has a circular motion about the axis 290 of the inner gear 29, without rotation around its own axis. Its motion may be referred to as one of curvilinear translation. It will also be observed that each of the five pistons 11 is double-acting (i.e., powered by the pressure fluid both inwardly and outwardly); the five pistons have their axes in a single plane and stroke in a common cylinder block (the cluster of cylinders 9). Each has a motion which is pure harmonic along its axis, and transmits pure axial thrust in either direction.

The device, used as a motor as above described, is particularly suited to slow speed operation with high torque capabilities. It is adapted for use as a pump by putting in power via the gearing and utilizing each cylinder and piston means 7 as a double-acting pump for pumping the hydraulic fluid.

FIGS. 9 and 10 illustrate a modification wherein the housing, designated 17a to distinguish it from housing 17, comprises pentagonal sections 131 and 133 having partitions 135 and 137, and a right-hand side wall 139 as shown in FIG. 9. The central gear 29 is journalled in the partitions 135 and 137 and has a center shaft 141 extending out through a central opening 143 in the side wall 139. Only one outer gear 45 is provided (at position A) journalled in the partitions, and carrying its re spective outer crank pin 3. The other four outer crank pins 3 are on crankshafts 145 (instead of gears 45) journalled in the partitions. On the end of each of these crankshafts between the partition 137 and the side wall 139 is an eccentric 147, and the single outer gear 45 carries a similar eccentric 147. The five eccentrics are interconnected by parallel linkage means generally designated 149. More particularly, this linkage means is a single rigid link constituted by a circular disk having openings 151 in which the eccentrics are journalled and a central opening 153 receiving the shaft 141 and considerably larger than the latter to permit circular motion (curvilinear translation) of the disk 149 about the axis of the shaft 141 with a radius corresponding to the eccentricity of each eccentric 147 relative to its respective shaft 145 or gear 45, without rotation of the disk about its own axis. The eccentrics and the disk constitute means for interconnecting the outer crank pins 3 with one another and with the inner pin 1 via the gear 45 and the gear 29.

The operation of the device shown in FIGS. 9 and 10 as a motor is generally the same as that of the device shown in FIGS. 1-8, with the difference that the outer crank pins 3 are maintained in the correct phase relative to one another by their interconnection via eccentrics 147 and the parallel linkage disk 149 (instead of by having five outer gears 45 as in the device of FIGS. 1-8).

A further modification of the above which is contemplated is one involving essentially the same constructions as above described, but with the central gear 29 and the pin 1 thereon held fixed, and the housing mounted for rotation so that the outer gears 45 (or single gear 45 in the case of FIGS. 9 and 10) are adapted for planetary motion about the central gear. In the operation of such a device as a motor, power would be taken off the housing (for example, by providing a power take-off gear rotatable with the housing), and in the operation of such a device as a pump, the housing would be positively rotated (for example, by providing a power input gear rotatable with the housing).

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attainedf As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings should be interpretative and not in a limiting sense.

What is claimed is:

1. An expansible chamber device comprising an inner pin, a plurality of outer crank pins rotatable about outer axes parallel to the axis of the inner pin spaced at intervals around a circle surrounding said inner pin, means interconnecting said outer crank pins and said inner pin and interconnecting said outer crank pins with one another, a cluster of cylinder and piston means, one for each outer crank pin, each cylinder and piston means comprising a cylinder element, a piston in the cylinder element and a piston rod element extending from the piston out of one end of the cylinder element, each cylinder and piston means extending outwardly from said inner pin spaced at angular intervals around said inner pin with one of said cylinder and piston rod elements of each cylinder and piston means connected to said inner pin and the other of said elements thereof connected to the respective outer crank pin, and means for controlling the supply and exhaust of fluid to and from opposite ends of each of said cylinder elements, wherein said inner pin is a crank pin on a central crank journalled for rotation in a frame of the device, wherein the center of said cluster is rotatable with said inner pin about the axis of said central crank, wherein the outer crank pins are on outer cranks journalled for rotation in the frame on outer axes parallel to the axis of the central crank spaced at equal intervals around said circle with said circle centered in the axis of the central crank and wherein said cylinder and piston means are rigidly interconnected together in said cluster for relative circular motion of the entire cluster as a unit on said inner pin about the axis of the central crank without rotation of the cluster around its own axis, wherein said interconnecting means comprises a central gear comprising said central crank and at least one outer gear comprising an outer crank in mesh with said central gear, said gears having a one-to-one gear ratio, and said crank pins all having the same throw.

2. An expansible chamber device as set forth in claim 1 wherein said central gear has said inner crank pin thereon and each outer crank comprises an outer gear in mesh with the central gear and having a respective outer crank pin thereon, said interconnecting means comprising all said gear, and said central gear and all said outer gears having a one-to-one gear ratio.

3. An expansible chamber device as set forth in claim 2 wherein said cylinder elements extend radially outwardly from a central hub rotatably mounted on the crank pin of said central gear, and the piston rod elements extend radially outwardly from the outer ends of the cylinder elements and have their outer ends rotatably connected to the said crank pins of said outer gears.

4. An expansible chamber device as set forth in claim 1 wherein said central gear has said inner crank pin thereon, and one of said outer cranks comprises said one outer gear having an outer crank pin thereon, and

wherein each of said outer cranks including said outer gear has an eccentric thereon, said interconnecting means being constituted by said gears and by linkage means interconnecting said eccentrics.

5. An expansible chamber device as set forth in claim 4 wherein said linkage means comprises a single rigid link having openings in which the eccentrics are journalled.

6. An expansible chamber device as set forth in claim 5 wherein said rigid link is a disk.

7. An expansible chamber device as set forth in claim 1 wherein said means for controlling the supply and exhaust of fluid comprises a sleeve at the center of the cluster, a series of fluid connections between the sleeve and the outer ends of the cylinders, a series of fluid connections between the sleeve and the inner ends of the cylinders, and a fluid distributor having a section rotatable in the sleeve.

8. An expansible chamber device as set forth in claim 2 wherein said means for controlling the supply and exhaust of fluid comprises a sleeve at the center of the cluster coaxial with the inner pin, a series of fluid connections between the sleeve and the outer ends of the cylinders, a series of fluid connections between the sleeve and the inner ends of the cylinders, and a fluid distributor having a section journalled in the frame coaxial with the central gear, and an eccentric section rotatable in the sleeve.

9. An expansible chamber device as set forth in claim 1 wherein said interconnecting means maintains the crank pins in such relation that each outer crank pin passes through its inner and outer dead center positions at the same time as the inner crank pin passes through its respective inner and outer dead center positions.

10. An expansible chamber device as set forth in claim 9 wherein said interconnecting means maintains certain of the outer crank pins out of phase with the other outer cran pins.

11. An expansible chamber device comprising an inner pin, a plurality of outer crank pins rotatable about outer axes parallel to the axis of the inner pin spaced at intervals around a circle surrounding said inner pin, means interconnecting said outer crank pins and said inner pin and interconnecting said outer crank pins with one another, a cluster comprising a hub rotatable on said inner pin and a plurality of cylinder and piston means, one for each outer crank pin, extending outwardly from the hub, each cylinder and piston means comprising a double-acting cylinder element, a piston in the cylinder element and a piston rod element extending from the piston out of one end of the cylinder element, one of said cylinder and piston rod elements of each cylinder and piston means being connected directly to said hub and the other of said elements thereof being connected directly to the respective outer crank pin, and means for controlling the supply and exhaust of fluid to and from opposite ends of each of said cylinder elements, said cylinder and piston means being rigidly interconnected together in said cluster on said hub for movement in unison, wherein said interconnecting means comprises a central gear comprising said central crank and at least one outer gear comprising an outer crank in mesh with said central gear, said gears having a one-to-one gear ratio, and said crank pins all having the same throw.

12. An expansible chamber device as set forth in claim 1 1 wherein said cylinder elements extend radially outwardly from the hub rotatably mounted on said inner pin, and the piston rod elements extend radially outwardly from the outer ends of the cylinder elements and have their outer ends connected directly to said outer crank pins.

13. An expansible chamber device as set forth in claim 11 wherein the outer crank pins are on outer cranks each comprising an outer gear in mesh with the central gear, said interconnecting means comprising all said gear, said central gear and all said outer gears having a one-to-one gear ratio.

14. An expansible chamber device as set forth in claim 11 having a central gear and wherein the outer crank pins are on outer cranks, one of which comprises said outer gear in mesh, and wherein each of said outer cranks including said outer gear has an eccentric thereon, said interconnecting means being constituted by said gears and by linkage means interconnecting said eccentrics.

15. An expansible chamber device as set forth in claim 14 wherein said linkage means comprises a single rigid link having openings in which the eccentrics are journalled.

16. An expansible chamber device as set forth in claim 15 wherein said rigid link is a disk.

17. An expansible chamber device as set forth in claim 11 wherein said inner pin is fixedand said outer crank pins are rotatable about said inner pin, and wherein said means for controlling the supply and exhaust of fluid comprises a sleeve at the center of the cluster, a series of fluid connections between the sleeve and the outer ends of the cylinders, a series of fluid connections between the sleeve and the inner ends of the cylinders, and a fluid distributor having a section rotatable in the sleeve.

18. An expansible chamber device as set forth in claim 17 wherein said means for controlling the supply and exhaust of fluid comprises a sleeve at the center of the cluster coaxial with the inner pin, a series of fluid connections between the sleeve and the outer ends of the cylinders, a series of fluid connections between the sleeve and the inner ends of the cylinders, and a fluid distributor having a section journalled in the frame coaxial with the central gear, and an eccentric section rotatable in the sleeve. 

1. An expansible chamber device comprising an inner pin, a plurality of outer crank pins rotatable about outer axes parallel to the axis of the inner pin spaced at intervals around a circle surrounding said inner pin, means interconnecting said outer crank pins and said inner pin and interconnecting said outer crank pins with one another, a cluster of cylinder and piston means, one for each outer crank pin, each cylinder and piston means comprising a cylinder element, a piston in the cylinder element and a piston rod element extending from the piston out of one end of the cylinder element, each cylinder and piston means extending outwardly from said inner pin spaced at angular intervals around said inner pin with one of said cylinder and piston rod elements of each cylinder and piston means connected to said inner pin and the other of said elements thereof connected to the resPective outer crank pin, and means for controlling the supply and exhaust of fluid to and from opposite ends of each of said cylinder elements, wherein said inner pin is a crank pin on a central crank journalled for rotation in a frame of the device, wherein the center of said cluster is rotatable with said inner pin about the axis of said central crank, wherein the outer crank pins are on outer cranks journalled for rotation in the frame on outer axes parallel to the axis of the central crank spaced at equal intervals around said circle with said circle centered in the axis of the central crank and wherein said cylinder and piston means are rigidly interconnected together in said cluster for relative circular motion of the entire cluster as a unit on said inner pin about the axis of the central crank without rotation of the cluster around its own axis, wherein said interconnecting means comprises a central gear comprising said central crank and at least one outer gear comprising an outer crank in mesh with said central gear, said gears having a one-toone gear ratio, and said crank pins all having the same throw.
 2. An expansible chamber device as set forth in claim 1 wherein said central gear has said inner crank pin thereon and each outer crank comprises an outer gear in mesh with the central gear and having a respective outer crank pin thereon, said interconnecting means comprising all said gear, and said central gear and all said outer gears having a one-to-one gear ratio.
 3. An expansible chamber device as set forth in claim 2 wherein said cylinder elements extend radially outwardly from a central hub rotatably mounted on the crank pin of said central gear, and the piston rod elements extend radially outwardly from the outer ends of the cylinder elements and have their outer ends rotatably connected to the said crank pins of said outer gears.
 4. An expansible chamber device as set forth in claim 1 wherein said central gear has said inner crank pin thereon, and one of said outer cranks comprises said one outer gear having an outer crank pin thereon, and wherein each of said outer cranks including said outer gear has an eccentric thereon, said interconnecting means being constituted by said gears and by linkage means interconnecting said eccentrics.
 5. An expansible chamber device as set forth in claim 4 wherein said linkage means comprises a single rigid link having openings in which the eccentrics are journalled.
 6. An expansible chamber device as set forth in claim 5 wherein said rigid link is a disk.
 7. An expansible chamber device as set forth in claim 1 wherein said means for controlling the supply and exhaust of fluid comprises a sleeve at the center of the cluster, a series of fluid connections between the sleeve and the outer ends of the cylinders, a series of fluid connections between the sleeve and the inner ends of the cylinders, and a fluid distributor having a section rotatable in the sleeve.
 8. An expansible chamber device as set forth in claim 2 wherein said means for controlling the supply and exhaust of fluid comprises a sleeve at the center of the cluster coaxial with the inner pin, a series of fluid connections between the sleeve and the outer ends of the cylinders, a series of fluid connections between the sleeve and the inner ends of the cylinders, and a fluid distributor having a section journalled in the frame coaxial with the central gear, and an eccentric section rotatable in the sleeve.
 9. An expansible chamber device as set forth in claim 1 wherein said interconnecting means maintains the crank pins in such relation that each outer crank pin passes through its inner and outer dead center positions at the same time as the inner crank pin passes through its respective inner and outer dead center positions.
 10. An expansible chamber device as set forth in claim 9 wherein said interconnecting means maintains certain of the outer crank pins out of phase with the other outer cran pins.
 11. An expansible chAmber device comprising an inner pin, a plurality of outer crank pins rotatable about outer axes parallel to the axis of the inner pin spaced at intervals around a circle surrounding said inner pin, means interconnecting said outer crank pins and said inner pin and interconnecting said outer crank pins with one another, a cluster comprising a hub rotatable on said inner pin and a plurality of cylinder and piston means, one for each outer crank pin, extending outwardly from the hub, each cylinder and piston means comprising a double-acting cylinder element, a piston in the cylinder element and a piston rod element extending from the piston out of one end of the cylinder element, one of said cylinder and piston rod elements of each cylinder and piston means being connected directly to said hub and the other of said elements thereof being connected directly to the respective outer crank pin, and means for controlling the supply and exhaust of fluid to and from opposite ends of each of said cylinder elements, said cylinder and piston means being rigidly interconnected together in said cluster on said hub for movement in unison, wherein said interconnecting means comprises a central gear comprising said central crank and at least one outer gear comprising an outer crank in mesh with said central gear, said gears having a one-to-one gear ratio, and said crank pins all having the same throw.
 12. An expansible chamber device as set forth in claim 11 wherein said cylinder elements extend radially outwardly from the hub rotatably mounted on said inner pin, and the piston rod elements extend radially outwardly from the outer ends of the cylinder elements and have their outer ends connected directly to said outer crank pins.
 13. An expansible chamber device as set forth in claim 11 wherein the outer crank pins are on outer cranks each comprising an outer gear in mesh with the central gear, said interconnecting means comprising all said gear, said central gear and all said outer gears having a one-to-one gear ratio.
 14. An expansible chamber device as set forth in claim 11 having a central gear and wherein the outer crank pins are on outer cranks, one of which comprises said outer gear in mesh, and wherein each of said outer cranks including said outer gear has an eccentric thereon, said interconnecting means being constituted by said gears and by linkage means interconnecting said eccentrics.
 15. An expansible chamber device as set forth in claim 14 wherein said linkage means comprises a single rigid link having openings in which the eccentrics are journalled.
 16. An expansible chamber device as set forth in claim 15 wherein said rigid link is a disk.
 17. An expansible chamber device as set forth in claim 11 wherein said inner pin is fixed and said outer crank pins are rotatable about said inner pin, and wherein said means for controlling the supply and exhaust of fluid comprises a sleeve at the center of the cluster, a series of fluid connections between the sleeve and the outer ends of the cylinders, a series of fluid connections between the sleeve and the inner ends of the cylinders, and a fluid distributor having a section rotatable in the sleeve.
 18. An expansible chamber device as set forth in claim 17 wherein said means for controlling the supply and exhaust of fluid comprises a sleeve at the center of the cluster coaxial with the inner pin, a series of fluid connections between the sleeve and the outer ends of the cylinders, a series of fluid connections between the sleeve and the inner ends of the cylinders, and a fluid distributor having a section journalled in the frame coaxial with the central gear, and an eccentric section rotatable in the sleeve. 